In 2001 Ukraine presented heavily modernized version of BMP-1 (BMP-1U by certain sources). Main difference from the basic BMP-1 is the replacement of the original armament by the new weapons station Shkval (Squall).
This weapons station was developed for light armored vehicles to increase their combat effectiveness. What catches the eye is the attempt of the Ukrainians to create their own 'Kliver' weapons station (similar system developed in Russia earlier), but from the domestic components. 'Shkval' consist of 30mm autocannon KBA-2 (analog of the Russian 2A72), double anti-tank launcher 'Konkurs1 (or Red Arrow can be used as well) and 30mm automatic grenade launcher AGS-17 'Plamya' (Flame). Although this system is new, it has it's own advantages: anti-tank and grenade launcher, auto-cannon as well as the ammunition are in widespread use all over the world. This in regards eliminates shortage of ammunition, makes it easy to maintain and lower the cost of license production if necessary. Since new weapon station required more room installation was accomplished at the cost of cutting down infantry squad to 6 people rather then 8 in original vehicle.
Aside from upgrades mentioned above the following was installed: flotation sides-skirts, drive sprocket and tracks from the BMP-2.